Northern Indiana tea party group Kosciusko Silent No More will join the effort to place the state's gay marriage ban in the constitution, President Monica Boyer announced Wednesday. The organizers of Freedom Indiana, which is opposing the amendment, meanwhile announced that Indianapolis media giant Emmis Communications was joining its effort.

The marking of sides comes as lawmakers prepare for their annual session in January. Supporters of limiting marriage to being between one man and one woman say a constitutional amendment is needed to keep the courts from legalizing gay marriage in Indiana. The state already bans gay marriage by law, but lawmakers began the lengthy process of placing the ban in the constitution in 2011.

If lawmakers sign off a second time on the strengthened ban, it would be placed on the ballot for voters to consider next November.

The ban won overwhelming support from Democrats and Republicans in 2011, but national attitudes on the issue have changed in the last few years, and Indiana leaders seem to have noticed. Fourteen states and Washington, D.C., now allow gay marriage. Illinois lawmakers passed a measure Tuesday that would legalize same-sex marriage; the governor has said he will sign it.

Freedom Indiana, which launched over the summer to oppose the amendment, has the support of Indiana corporate giants Eli Lilly and Cummins, along with universities and other high-profile organizations. Their central argument has been that the ban would keep talented job-seekers and businesses from moving to Indiana.

"Indiana has traditionally had a friendly business environment that is the backbone of the Hoosier economy," Emmis CEO Jeff Smulyan said in statement.

But Boyer said Wednesday that lawmakers and voters should consider the religious freedom of residents who believe marriage can only be between one man and one woman.

"Redefining marriage forces everyone else, including churches, schools, and business owners, to affirm homosexual relationships, denying people their religious freedom and opinion," she said in a statement.

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